host-common/address_space_device.h

// Copyright 2019 The Android Open Source Project
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#pragma once

#include <inttypes.h>

extern "C" {

struct AddressSpaceHwFuncs;

struct AddressSpaceCreateInfo {
    uint32_t type;
    uint64_t physAddr;
    bool fromSnapshot;
};

typedef uint32_t (*address_space_device_gen_handle_t)(void);
typedef void (*address_space_device_destroy_handle_t)(uint32_t);
typedef void (*address_space_device_tell_ping_info_t)(uint32_t handle, uint64_t gpa);
typedef void (*address_space_device_ping_t)(uint32_t handle);
typedef int (*address_space_device_add_memory_mapping_t)(uint64_t gpa, void *ptr, uint64_t size);
typedef int (*address_space_device_remove_memory_mapping_t)(uint64_t gpa, void *ptr, uint64_t size);
typedef void* (*address_space_device_get_host_ptr_t)(uint64_t gpa);
typedef void* (*address_space_device_handle_to_context_t)(uint32_t handle);
typedef void (*address_space_device_clear_t)(void);
// virtio-gpu-next
typedef uint64_t (*address_space_device_hostmem_register_t)(const struct MemEntry *entry);
typedef void (*address_space_device_hostmem_unregister_t)(uint64_t id);
typedef void (*address_space_device_ping_at_hva_t)(uint32_t handle, void* hva);
// deallocation callbacks
typedef void (*address_space_device_deallocation_callback_t)(void* context, uint64_t gpa);
typedef void (*address_space_device_register_deallocation_callback_t)(void* context, uint64_t gpa, address_space_device_deallocation_callback_t);
typedef void (*address_space_device_run_deallocation_callbacks_t)(uint64_t gpa);
typedef const struct AddressSpaceHwFuncs* (*address_space_device_control_get_hw_funcs_t)(void);

struct address_space_device_control_ops {
    address_space_device_gen_handle_t gen_handle;
    address_space_device_destroy_handle_t destroy_handle;
    address_space_device_tell_ping_info_t tell_ping_info;
    address_space_device_ping_t ping;
    address_space_device_add_memory_mapping_t add_memory_mapping;
    address_space_device_remove_memory_mapping_t remove_memory_mapping;
    address_space_device_get_host_ptr_t get_host_ptr;
    address_space_device_handle_to_context_t handle_to_context;
    address_space_device_clear_t clear;
    address_space_device_hostmem_register_t hostmem_register;
    address_space_device_hostmem_unregister_t hostmem_unregister;
    address_space_device_ping_at_hva_t ping_at_hva;
    address_space_device_register_deallocation_callback_t register_deallocation_callback;
    address_space_device_run_deallocation_callbacks_t run_deallocation_callbacks;
    address_space_device_control_get_hw_funcs_t control_get_hw_funcs;
};

struct address_space_device_control_ops*
get_address_space_device_control_ops(void);

struct QAndroidVmOperations;
void address_space_set_vm_operations(const QAndroidVmOperations* vmops);

struct AddressSpaceHwFuncs {
    /* Called by the host to reserve a shared region. Guest users can then
     * suballocate into this region. This saves us a lot of KVM slots.
     * Returns the relative offset to the starting phys addr in |offset|
     * and returns 0 if successful, -errno otherwise. */
    int (*allocSharedHostRegion)(uint64_t page_aligned_size, uint64_t* offset);
    /* Called by the host to free a shared region. Only useful on teardown
     * or when loading a snapshot while the emulator is running.
     * Returns 0 if successful, -errno otherwise. */
    int (*freeSharedHostRegion)(uint64_t offset);
    
    /* Versions of the above but when the state is already locked. */
    int (*allocSharedHostRegionLocked)(uint64_t page_aligned_size, uint64_t* offset);
    int (*freeSharedHostRegionLocked)(uint64_t offset);

    /* Obtains the starting physical address for which the resulting offsets
     * are relative to. */
    uint64_t (*getPhysAddrStart)(void);
    uint64_t (*getPhysAddrStartLocked)(void);

    /* Version of allocSharedHostRegionLocked but for a fixed offset */
    int (*allocSharedHostRegionFixedLocked)(uint64_t page_aligned_size, uint64_t offset);
};

extern const struct AddressSpaceHwFuncs* address_space_set_hw_funcs(
    const struct AddressSpaceHwFuncs* hwFuncs);
const struct AddressSpaceHwFuncs* get_address_space_device_hw_funcs(void);

} // extern "C"